249 research outputs found
Essentials of business law / Ewan MacIntyre.
No full textIncludes bibliographical references and index.xxxiii, 464 pages.
Structure and dynamics of evolving complex networks
No full textThis thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel UniversityThe analysis of large disordered complex networks has recently received enormous attention motivated by both academic and commercial interest. The most important results in this discipline have come from the analysis of stochastic models which mimic the growth and evolution of real networks as they change over time. The purpose of this thesis is to introduce various novel processes which dictate the development of a network on a small scale, and use techniques learned from statistical physics to derive the dynamical and structural properties of the network on the macroscopic scale. We introduce each model as a set of mechanisms determining how a network changes over a small period in time, from these rules we derive several topological
properties of the network after many iterations, most notably the degree distribution. 1. In the rst mechanism, nodes are introduced and linked to older nodes in the network in such a way as to create triangles and maintain a high level of clustering. The mechanism resembles the growth of a citation network and we demonstrate analytically that the mechanism introduced su ces to explain the power-law form commonly found in citation distributions. 2. The second mechanism involves edge rewiring processes - detaching one end of an edge and reattaching it, either to a random node anywhere in the network or to one selected locally. 3. We analyse a variety of processes based around a novel fragmentation mechanism. 4. The nal model concerns the problem of nding the electrical resistance across a network. The network grows as a random tree, as it grows the distribution of resistance converges towards a steady state solution. We nd an application of the relatively recent concept of a random Fibonacci sequence in deriving the rate of convergence of the mean.EPSR
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Applied Social Science for Early Years
No full textApplying social science subjects such as psychology, sociology, social policy and research methods to Early Years can help to raise standards and ensure good practice. These subjects inform much of the academic curriculum within many Early Years programmes and are subjects that make an important contribution to understanding children’s behaviour, growth and development. The book identifies, analyses and assesses how social science enriches Early Years as opposed to regarding Early Years and social science as distinct. Each chapter imaginatively introduces the main learning objectives and includes formative activities, which apply social science to particular themes to aid students’ cognitive skills
We carry the light, comprising : i) Writing in lockdown: exploring the impact of the Covid-19 pandemic on writers' creativity, ii) We carry the light, a family novel set in Scotland during the pandemic
No full textThis paper examines the impact of the Covid-19 pandemic on writers’ practice during the periods that social distancing restrictions were in place. The study focuses on – but is not limited to – the first UK lockdown, which began on 23rd March 2020.
Structured interviews were conducted with five writers, with an additional person responding to the questions in writing. This group included writers of fiction and non-fiction, as well as poets. Interviewees were at various points of their careers, ranging from an undergraduate creative writing student to a prize-winning author who has been publishing for over thirty years. Through these interviews, the impact of the pandemic on writing was explored in three main areas: the impact of emotions on the writing process; the effect Covid had on conditions needed for writing; and the ability of writers to find and/or act on inspiration.
Incorporating evidence from these interviews – as well as from writing anthologies, newspaper articles, and literature relating to the pandemic – this study demonstrates that the pandemic did have a noticeable impact on writers’ creativity. Although two writers wrote more during lockdown, nearly all described the negative impact emotions had on their ability and/or motivation to write. Where the pandemic disrupted the conditions they need to write, writers wrote nothing, or significantly less than pre-pandemic; writers whose children lived with them during this time were most affected. Some noticed a negative correlation between finding/acting on inspiration and social distancing restrictions. Writers reflected on the impact of the pandemic and were able to identify positive and negative aspects that were a result of the restrictions, such as the benefits in terms of inclusion at literary events. The findings presented in the final section show the importance of learning from and recording the pandemic through writing."This work was supported by the Ewan and Christine Brown Postgraduate Studentship in the Arts and Humanities. I would, therefore, like to express my heartfelt gratitude to Ewan and Christine Brown for the financial support that allowed me to undertake this doctoral research.”--Fundin
Fossil fuel divestment, directors’ duties, and derivative claims: McGaughey and Davies v. USS Ltd and its directors
No full textA Climate Change Laws of the World insight In July 2023, at that time the hottest ever month in human history, the UK Court of Appeal gave judgment in McGaughey and Davies v. USS Ltd and its Directors [2023] EWCA Civ 873. The author of this note, Professor Ewan McGaughey, and his colleague, Professor Neil Davies, had undertaken the largest crowdfunded drive in the UK so far, to sue the board of directors personally to reverse (the roughly) 30% cuts to defined benefit pensions, and to require the UK’s biggest pension fund, the Universities Superannuation Scheme (USS), to divest of its fossil fuels assets. Out of court, after the Truss mini-budget, years of strikes, and shortly after the complainants got leave to the Court of Appeal, USS capitulated: the CEO announced his resignation, and USS declared it would reverse the pension cuts. Despite this victory, McGaughey and Davies went on to lose in the Court of Appeal, but by then they had already succeeded in most of their goals. The key issue where they had limited success was in fossil fuel divestment. The focus of this Climate Change Laws of the World note is why they lost on the fossil fuel claim, but also how the case sets a positive precedent for beneficiaries seeking to uphold directors’ duties, thus it may be instructive for the future wave of litigation against directors complicit in climate damage
Numerical models of Hall thruster ionization oscillations
No full textThesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2016.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (pages 141-143).In this thesis, low frequency ionization oscillations in Hall thrusters resembling the breathing mode are studied through computational simulation. The relationship between wall erosion and discharge current oscillations is analyzed using particle-in-cell simulation, and a series of parametric simulations is used to determine the effects of macro-particle size, floating body potential, electron injection region, ion time step size, grid refinement, heavy particle mass reduction, and an artificial permittivity factor. These studies help to determine the parameters that will produce accurate simulations in the future, and identify the parts of the model that need improvement. One-dimensional steady and unsteady Hall thruster models, as well as a generalized sheath model are then developed, and the effects of the parameters that determine stability on the thruster's operating conditions are determined.by Ewan Samuel Kay.S.M
The impact of signal variability on COVID-19 epidemic growth rate estimation from wastewater surveillance data.
No full textTesting samples of wastewater for markers of infectious disease became a widespread method of surveillance during the COVID-19 pandemic. While these data generally correlate well with other indicators of national prevalence, samples that cover localised regions tend to be highly variable over short time scales. Here we introduce a procedure for estimating the real-time growth rate of pathogen prevalence using time series data from wastewater sampling. The number of copies of a target gene found in a sample is modelled as time-dependent random variable whose distribution is estimated using maximum likelihood. The output depends on a hyperparameter that controls the sensitivity to variability in the underlying data. We apply this procedure to data reporting the number of copies of the N1 gene of SARS-CoV-2 collected at water treatment works across Scotland between February 2021 and February 2023. The real-time growth rate of the SARS-CoV-2 prevalence is estimated at all 121 wastewater sampling sites covering a diverse range of locations and population sizes. We find that the sensitivity of the fitting procedure to natural variability determines its reliability in detecting the early stages of an epidemic wave. Applying the same procedure to hospital admissions data, we find that changes in the growth rate are detected an average of 2 days earlier in wastewater than in hospital admissions. In conclusion, this paper provides a robust method to generate reliable estimates of epidemic growth from highly variable data. Applying this method to samples collected at wastewater treatment works provides highly responsive situational awareness to inform public health
Disfluency in dialogue:an intentional signal from the speaker?
No full textDisfluency is a characteristic feature of spontaneous human speech, commonly seen as a consequence of problems with production. However, the question remains open as to why speakers are disfluent: Is it a mechanical by-product of planning difficulty, or do speakers use disfluency in dialogue to manage listeners' expectations? To address this question, we present two experiments investigating the production of disfluency in monologue and dialogue situations. Dialogue affected the linguistic choices made by participants, who aligned on referring expressions by choosing less frequent names for ambiguous images where those names had previously been mentioned. However, participants were no more disfluent in dialogue than in monologue situations, and the distribution of types of disfluency used remained constant. Our evidence rules out at least a straightforward interpretation of the view that disfluencies are an intentional signal in dialogue
Analyzing the Effect of Deceiving Agents in a System of Self-Driving Cars at an intersection - a computational model
No full textThe creation of protocols for autonomous intersection management is an active research topic with the potential of increasing the capacity of intersections addressing the increasing demand on roads. Most of the proposed protocols assume that all the vehicles involved will behave pro-socially, that is, in a way that improves the outcome of the system over their individual gain. We simulated three different autonomous intersection protocols, two centralized and one decentralized, introducing some egoistic agents that we call deceiving vehicles. Deceiving vehicles may decide to transmit false information while using a protocol if they detect that doing so can result in a lower delay in the intersection. Our simulations show that in two of the protocols, it is possible for a deceiving vehicle to experience lower delay times compared to its non-deceiving counterparts. Additionally, as more deceiving vehicles enter the system the overall capacity of an intersection can be reduced, increasing delays for non-deceiving vehicles which creates an incentive for more vehicles to deceive. We pose that, given that vehicles have an incentive to deceive, autonomous intersection protocol's authors need to consider deceiving vehicles in their design and include measures to prevent them, thus avoiding the performance degradation they produce.La creación de protocolos de manejo autónomo de intersecciones es un tema de investigación activo que tiene el potencial de aumentar la capacidad de las intersecciones aportando a la solución del problema del creciente aumento en la demanda en las vías. La mayoría de los protocolos propuestos asumen que todos los vehículos se comportan de manera prosocial, es decir, que actúan de una manera que beneficia al sistema sobre su propio beneficio. Nosotros simulamos tres protocolos de intersección autónomos, dos centralizados y uno descentralizado, introduciendo algunos agentes egoístas que llamamos vehículos engañosos. Los vehículos engañosos pueden decidir transmitir información falsa cuando usan un protocolo si detectan que hacerlo puede resultar una demora menor en la intersección. Nuestras simulaciones muestran que, en dos de los protocolos, es posible que los vehículos engañosos experimenten demoras menores frente a sus contrapartes no-engañosos. Asimismo, conforme más vehículos engañosos son introducidos en el sistema, la capacidad total de la intersección se ve reducida, aumentando las demoras para los vehículos que no son engañosos lo que genera un incentivo para que más vehículos sean engañosos. Proponemos que, dado que los vehículos tienen incentivos para engañar, los autores de protocolos de intersecciones autónomas deben considerar los vehículos engañosos en su diseño e incluir medida para prevenirlos, evitando así la degradación en rendimiento que producen.MaestríaSistemas Inteligente
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